Designed and built by Bauhaus founder Walter Gropius in 1911, this factory, which has been producing shoe lasts for over 100 years, is regarded as the world's first modernist factory building (it was given Unesco World Heritage status in 2011). Sections of the building have been turned into a gallery that focuses on Gropius' life, the Bauhaus movement, the history of the Fagus company and footwear in general. Guided factory tours are recommended, but you can also go solo.
It's just over a five-minute walk to the factory from Alfeld station, serviced regularly by regional trains from Hanover (€11.40, 30 minutes), or a 30-minute drive from Hildesheim.